Addiction, increasingly discerned as a heterogeneous brain disorder, is one of the most distinct psychiatric pathologies in that its management includes often non-overlapping, resources from the biological, psychological, medical, economic, social, and legal realms. Despite various researches, till now there are no dependably effective treatments of addiction. This may result from a lack of acknowledgement of the etiology and pathophysiology of this disease and also from the lack of concern into the potential differences among patients in the way they interact compulsively with their drug. This book presents an outlook of general considerations and pathophysiology of addiction. The information available in this book would serve as a valuable guide for those involved in the field of addiction control.